Tie rod for concrete forms

ABSTRACT

A tie rod for concrete forms which is formed from a length of wire and has defined adjacent opposite ends thereof latchreceiving portions of substantially square cross-section outwardly subtended by flanges of greater dimension than the diameter of the wire.

United States Patent [191' Daniels, Jr.

1 1 May 6,1975

[ TIE ROD FOR CONCRETE FORMS [76] Inventor: Ransom .1. Daniels, Jr., 93

Brookhaven Drive, Glastonbury, Conn. 06033 [22] Filed: Jan. 26, 1973 211 App]. No.: 326,598

Related US. Application Data [62] Division of Ser. No. 141,576, May 10, 1971, Pat. No.

2,245,559 6/1941 Kinninger 249/216 X 2,825,956 3/1958 Shoemakerm, 249/41 X 3,007,221 11/1961 Kenney 249/219 W X 3,010,175 11/1961 Shoemaker.... 249/41 3,075,272 1/1963 Buyken 1 249/214 3,260,495 7/1966 Buyken 249/41 X 3,327,988 6/1967 Bridges 249/213 3,633,867 1/1972 Eriksson v 249/42 X 3,734,453 5/1973 Bailey 249/213 3,767,158 10/1973 Mikus 249/40 X Primary ExaminerFrancis S. Husar Assistant ExaminerJ0hn S. Brown Attorney, Agent, or FirmDeLio and Montgomery [57] ABSTRACT A tie rod for concrete forms which is formed from a length of wire and has defined adjacent opposite ends thereof latch-receiving portions of substantially square cross-section outwardly subtended by flanges of greater dimension than the diameter of the wire.

4 Claims, 14 Drawing Figures PATENTEDHAY 61975 3.88 1.68

sum 1 or 3 E 5.7; E2. 214- P153. 5. Fig.5 1

TIE ROI) FOR CONCRETE FORMS This application is a division of application Ser. No. 141,576 filed May 10, l97l and now US. Pat. No. 3,746,297.

This invention relates to forms for pouring concrete and more particularly relates to a tie rod for holding such forms in a given relationship.

Concrete foundation walls are generally poured between two sets of forms disposed in essentially parallel relationship and defining therebetween a dimension for the thickness of the concrete wall. Such opposed spaced apart walls are generally held in a fixed relationship against the immense weight of the poured concrete by tie rods having abutment surfaces which act against wedging or latching members.

The most widely used type of tie rod is a so-called button end tie rod which has a washer-like member swaged to the ends thereof to provide a flange which acts against a wedge-like member having an elongated slot with an enlarged key at one end thereof. These tie rods extend through spaced apart form sections and carry dish-shaped washers which bear against the inside of the form sections and hold the sections against relative movement toward each other. The tie rods may extend outwardly of the sections 4 to 8 inches to accommodate so-called waling strips running horizontally behind the form section and stiff backing running vertically behind the waling. A wedge or dog is then fitted over the button end and the waling and stiff backing is held between the form walls and the dog to rigidize and reinforce the form walls.

These button end tie rods are relatively expensive to form. The production thereof requires the forming of two flattened portions, positioning of the dished washers adjacent the flattened portions, positioning of smaller washers adjacent the ends thereof, and swaging of the rod on opposite sides of the end washer.

Another form of the rods used in a forming system wherein latching members are pivotally mounted to the form sections comprises a length of wire or rod stock which has been flattened either throughout its length or at the extremities thereof in a first plane to form a generally rectangular crOss section and then within the area of first flattening has been formed in a perpendicular plane so as to form indentations perpendicular to the first planes and flanges or abutment surfaces adapted to be engaged by a latch on the concrete form sections.

While this type of tie rod has enjoyed popularity and is a relatively inexpensive disposable item, it has serious defects in that it may only be inserted in one plane in the form to be properly engaged by the form latch. Additionally, if the latching device is worn, the tie is not correctly formed to provide the proper abutment surfaces, or it is not properly placed to receive the latching member, it is not uncommon for the form wall to blow under weight of poured concrete.

Generally speaking, all tie rods act to resist the pressure of the concrete between two opposed sets of form sections and if one tie blows it is highly likely that all other ties along the two adjoining sections will blow and the poured concrete will seep out into an unusable mass.

Moreover, these tie rods where flattened throughout their length have a greater periphery than the original round stock which provides a larger moisture creepage path from one side of the cured wall to the other.

Accordingly, the present invention provides a new and improved tie rod construction which is adjustable for most concrete forming systems and which may be utilized in either the fabricated form systems using waling and stiff backing or the form systems using pivotal latching members. A tie rod construction embodying the present invention is much less expensive in manufacture than the aforementioned button end tie rod and further eliminates the requirement for rolling or flattening wire or rod stock along its length and then flattening in another direction as in the latching type of tie rod. The invention further provides a tie rod having greater tensile strength.

The present invention further provides a tie rod which is so formed that it may be inserted in either of two angular positions between opposed form sections and latched thereto in the latching system. The invention further provides a tie rod which is cylindrical throughout most of its length and therefore presents the least creepage path for moisture from one side of a concrete wall to the other.

Briefly stated, the invention in one form thereof comprises a length of wire of given diameter which is formed to have a portion of substantially cross-section area adjacent the end thereof outwardly subtended by an annular flange of greater diameter than the wire. The square portion is formed in mating die parts which define the substantially square section portion. While the wire is held in the die, the ends thereof are headed to define the flange and also a tool grasping portion if desired.

An object of this invention is to provide a new and improved tie rod for concrete forms, and a method of making the same.

Another object of this invention is to provide a new and improved tie rod construction for concrete forms having improved strength, and flexibility of use.

A further object of this invention is to provide a tie rod for concrete forms which is more economical in construction The features of the invention which are believed to be novel are particularly pointed out and definitely claimed in the concluding portion of this specification. The invention, however, both as to its construction and operation, together with further objects and advantages thereof may best be appreciated by reference to the following detail description taken in conjunction with the drawings, wherein:

FIG. I is a side elevational view of a portion of two adjoining sections of concrete forms together with a latching mechanism and tie rod therefor;

FIG. 2 is a view seen in the plane of lines 2-2 of FIG.

FIG. 3 is a view of one end of the tie rod formed in accordance with the invention;

FIG. 4 is an end view of the rod of FIG. 3;

FIGS. 5, 6 and 7 are sectional views seen in the plane of lines 5-5, 66 and 77 of FIG. 3;

FIG. 8 is a view of a die utilized in forming a tie rod in accordance with the invention together with the tie rod therein;

FIG. 9 is an end view of the die parts of FIG. 8 shown joined together with a tie rod therein;

FIG. I0 is an end view of a heading punch; and

FIG. 11 is a sectional view seen in the plane of line 11-11 of FIG. 8.

FIG. 12 is a view in cross-section showing another forming system in which a tie rod constructed in accordance with the invention may be used.

FIG. 13 is an enlarged end view ofa wedging member shown in FIG. 12; and

FIG. 14 is an enlarged view of a portion of the tie rod of FIG. 12.

A tie rod constructed embodying the invention is first disclosed in a forming system utilizing pivotal latching members.

FIG. 1 exemplifies two sections 12 and 13 of upright concrete forms, where each section may be of a multilayer plywood, and having rows (only one shown) of horizontally extending metal strips 14 affixed thereto by means of bolts or screws 15. A clamping or latching member 17 is pivotally mounted to section 13 adjacent one edge thereof by means of a headed bolt 18 extending into section 13 and strip 14. Latching member 17 has an elongated slot 19 defined therein to allow some lateral and longitudinal movement as well as pivotal movement. Sections 12 and 13 at each side thereof have defined therein a recess 16. Defined in strips 14 are generally L-shaped slots 20 communicating with the abutting vertical edge to receive therein a tie rod 21 as hereinafter more fully described. The tie rod 21 may be disposed in either of the form sections 12 and I3. Extending from strip 14 on section 12 is a further headed bolt or stud 23 adapted to be received in a slot 24 defined in latching member 17. Latching member 17 also has defined therein slots 25 adapted to engage a flange which provides an abutment on a tie rod 21 positioned in either of the form sections 12 and 13, as hereinafter described.

It is to be understood that the reference to the vertical and horizontal pertain to the form sections in their normal concrete position to receive or retain poured concrete. As will be further exemplified, the sections 12 and 13 have mating sections spaced horizontally therefrom to define the thickness of a wall that has been poured or to be poured.

With the construction thus far described in FIG. 1 it will be seen when the clamping member 17 is moved to the position shown in dotted line it will engage the headed stud or bolt 23 and also the tie rod 21, and latch the abutting sections 12 and 13 together.

As disclosed, the tie rod 21 comprises a length of wire or rod stock generally in cylindrical form which is flattened at portions 26 adjacent the opposite ends thereof to provide locking means for the tie rods with respect to the concrete wall 27. Rod 21 further comprises latching sections 28 at either end thereof outwarclly subtended by annular flanges 29 and tool grasping portions 30. Defined on the rod just behind the rectangular portion 28 are small cars 28a which aid in positioning the opposed form sections and spacing them apart. The cars 28a reside across the diagonal of the latching section and will engage the back of strips 14 of the slots 20.

Also defined in rod 21 are annular sections 31 of reduced dimension and weakened section adapted to provide a breakoff point for the tie rod as hereinafter described.

The tool grasping section is formed in any desired shape so as to enable it to be grasped by a tool adapted to shear the flange portion 29 of the rod at plane 29a and allow removal of the latching member 17, subsequent to curing of the concrete.

With specific reference to FIG. 2, as the opposed form sections 12, 12' and others abutting thereto are erected in operative relationship, the rods 21 are inserted into the slots 20 and allowed to rest on the bottom thereof. Then the clamping members 17 are moved into the position shown in dotted line in FIG. 1 so as to engage the headed studs or bolts 23 in slots 24 and also the rectangular portion 28 in slots 25. Then the latching members 17 are positioned to engage the inner surfaces of flanges 29 and react thereagainst the weight of the concrete tending to separate the form sections. In this manner, adjoining form sections are latched together in parallel vertical relationship and opposite walls are held in predetermined spaced relation dependent on the length of the tie rods. It will be appreciated that the other vertical edge of form section 12 (not shown) will carry thereon a latching member 17. The other end of form section 13, (not shown) will have defined therein an L-shaped slot 20 adapted to receive a tie rod 21. It is to be further understood that along the abutting edges of the sections 12 and 13 there will be a plurality of the strips 14 defining the slots 20 and carrying the clamping and latching members 17 so that adjoining form sections may be clamped and latched together at a plurality of locations along their abutting vertical edges.

FIG. 8 exemplifies upper and lower die sections 32 and 33, respectively, shown in a parted relationship adapted to form a tie rod 21 as shown in FIGS. 2-7, together with a formed tie rod 21 therein In operation, the die parts 32 and 33 will form the tie rod 21. The die parts 32 and 33 each define communicating cavities 35 which form the substantially square or diamond-shaped portion 28. Inwardly of cavities 35 are communicating cavities 35a into which metal will flow during forming of portion 28 to define the ears 28a. Outwardly, beyond cavities 35 is a semi-circular cavity 36 in each die part to define flange 29. Extending outwardly from cavities 36 in each die part are cavities 37 defining a passage of generally triangular crosssection, better seen in FIG. 9 adapted to receive a matingly formed, generally triangular heading punch 38 as shown in FIG. 10.

The die parts 32 and 33 each define a cavity 41 adapted to receive inserts 42 which have forming surfaces 43 to define the weak areas 31. The inserts 42 are clamped in the cavities by set screws 44.

FIG. 8 exemplifies the die parts for forming only one operative end of a tie rod. It will be understood that other die parts are provided to identically form the other end of the rod. The other die parts are spaced a distance from die parts 32 and 33 determined by the desired dimension of the rod between flanges 29.

In operation, a desired length of rod or wire stock is placed in the lower die member and the upper die member is brought into engagement therewith with sufficient pressure to form the substantially square portions 28, the slightly protruding ears 28a and flats 26. At this time, the portion of the rod or wire extending outwardly beyond portion 28 is still cylindrical as indicated by the broken line 46, FIG. 8. While the die parts are still in engagement, the heading punch 38 is moved into cavities 37, to engage the end 46 of the rod or wire and expand it outwardly against the walls of the cavity to the triangular shape or the cavity as exemplified in FIG. 9. Prior to the heading operation, the three walls of the triangular cavity engage the extending end 46 of the wire at three points of tangency. During the heading operation, the metal of the rod or wire will flow outwardly to fill the triangular cavity and the cavities 36 to define the flanges 29. Then the heading punches 38 are withdrawn from each end, the die parts 32 and 33 opened, and the forming rod 21 expelled or removed from the die.

While the tool engaging portion 30 is shown as formed generally triangular in cross-section it may be formed in any convenient cross-section such as triangular, four-sided, or six-sided, so as to be received in the socket or cutout portion of a turning or shearing tool, and turned without slippage. The cross-sectional form of the turning portion 30 is not critical to the invention.

As thus formed, the tie rods 21 are inserted into the L-shaped slots of opposed and spaced form sections as they are erected or subsequent thereto in either of two angular relationships. Then, the latching members 17 are pivoted downwardly to the dotted line position shown in FIG. 1 to securely latch the forms together. The edges defining slots 25 will engage flanges 29 on opposite surfaces of portion 28 regardless of the position thereof. Thereafter, when all of the form sections, as exemplified by the sections 12 and 13, are joined and latched together, the concrete may be poured. The immense weight of the concrete attempting to separate the forms is reacted by inside surfaces 47 of the flange portions 29 to hold the form sections in the set position. In this situation, it will be realized that the tie rods 21 may be made in a variety of dimensions so as to accommodate the form sections for varying wall thicknesses. After the concrete wall 27 has cured, the form sections may be removed by first grasping the portion with a turning tool and producing a rotary or rotational motion thereon. This will cause the rods to shear off at the point 29a where portion 28 joins flange 29 since the latches l7 prevent any rotational movement of the rods. Then the clamping members 17 may be raised to full line position as shown in FIG. 1. The end portion 30 of a tie rod must be removed before the clamping member 17 may be raised due to the immense pressure exerted by the concrete when it is poured into the form and the resulting frictional engagement between the clamping member 17 and the inside surface of the flanges 29. After the forms have been removed, the rectangular clamp engaging sections 28 remain protruding on the concrete wall. As is customary in the masonry art, a laborer may strike these protruding edges with a hammer one or two times and the rod break at the weakened sections 31. Thereafter, the indentations left in the wall may be patched with an appropriate cement or grout.

The flattened portions 26 securely lock the tie rods into the finished wall, and the fact that the rods 23 are generally circular in cross-section presents a reduced peripheral path about which any moisture may flow from the exterior to the interior of the cured wall 27.

By way of example only, a tie rod embodying the invention may be formed from wires which have diameters of 0.2625; 0.274; or 0.28! and consequent crosssections of 0.0549; 0.590; and 0.0609 square inch. Using these size wires, the portion of substantially square cross-section 28 is fonned with flats of 0.234 to 0.236 inch having areas varying from 0.0548 to 0.0556 square inches. This dimension is utilized where the slots 20 are 0.250 inches. The cross-sectional areas of the portions are thus about 10 percent less than the crosssectional area of the wire. It is preferred that the crosssectional area of the portion 28 be no less than l5 percent less than the cross-sectional area of the wire to maintain the desired tensile strength of the rod. The diagonal across the square may be greater than the original diameter of the wire. However, the dimension across the flats of the square is less than the diameter of the wire stock. The diameter of the flange 29 is 0.400 inch and may have a thickness of approximately 0.10 inch. The length of the square cross-section portion 28 is approximately nine-sixteenth inch. With this construction, the latching member 17 will have large abutment surfaces beyond the square cross-sectional area regardless of the angular disposition of the tie rod in the slots 20.

The slots 20 are generally formed with a dimension across the vertical edges thereof of 0.250 inch. Thus, when the tie rods are inserted into the slots 20 they may slide in either of two defined angular positions apart and the flanges 29 extending beyond the flat surfaces thereof in all four directions will be properly positioned to be engaged and abutted by the latching members 17.

The dimensioning of the flats of the rectangular portion is such that the tie rod cannot be inserted in the slots 20 except in one of two angular positions.

The disclosed tie rod provides a tie rod of greater cross-section througout, resulting in greater tensional strength. Moreover, the circular peripheral shape throughout the length thereof provides a decreased moisture creepage path. The provision of the clamping section or area 28 of substantially square cross-section allows the tie rod to be operatively inserted into the slots 20 in any given position and, together with the annular flanges 29, insures that the clamping member 17 will have positive engagement with abutting surfaces to prevent outward movement of the form sections when the concrete is poured. Moreover, the provision of the latch receiving and clamping section 28 of essentially square cross-section which is substantially equal in area to the cross-section of the cylindrical tie or wire causes essentially no decrease in the tensional strength of the tie rod.

Another tie rod embodying the invention is shown in FIGS. 12-14 in a more conventional forming system. A tie rod 50 extends between form sections 51 and 52 which are generally plywood sections. The rod has flattened portions 53 disposed on either side of the center of the midpoint thereof. The flattened portions 53 provide a breakoff point and also position washers 54 on the inside of the form sections. The washers 54 positioned by the flats 53 serve to space the form sections 51 and S2 and further act as a seal to prevent concrete from escaping from the apertures 55 through which the rods pass. Rod 50 may extend a predetermined distance beyond form 52 or the distance of waling strips 56 and stiff backing 57 which are usually 2 inches X 4 inches lumber. The waling strips extend horizontally across the form sections to tie all of the form sections in one plane. The stiff backing is optional depending upon the thickness and height of the wall that is being poured. Formed adjacent the end of tie S0 is the square section 58 subtended by annular flange 59 shaped as previously described. Positioned on the rod about section 58 is a wedging member or dog 60.

The dog 60 is formed with a slot 61 and a key 62 of enlarged dimension adapted to fit over the flange 59. Then the dog, which is wedge-shaped, is driven down as by means of a hammer over the rectangular portion 58.

In operation, one of the form sections 51 or 52 is erected, the tie 50 is extended through the section 52 until the washer 54 limits further movement. Then the sections are braced in upright position, waled and stiffbacked and the dogs 60 wedged down on the rectangular section 58. Thereafter the section 51 is mounted over the other ends of the rod 50 and positioned with respect thereto by the washer 54, waled, stiff-backed and the dog 60 is inserted over the flange 59.

After the concrete has been poured and cured, the dogs 60 are removed together with the stiff-backing and waling. Then the extending ends may be struck with a hammer or otherwise deformed in any other manner until the rods break at the weakened flat section 53. Thereafter, the forms 51 and 52 are stripped from the wall.

In forming the tie 50, it is first necessary to position the washers 54 thereon. Then the predetermined length of stock is positioned in a die for forming as exemplified in FIG. 8. However, the die will be recessed at some portion thereof where the washer is temporarily located so that the washer will not be deformed when the die members close. Thereafter, the ends of the stock are headed as previously described while the rod is held in the die to form the flange 58 as previously described. ln this construction it is not necessary to define any particular shape on the end of the rod or a turning tool.

It will be apparent that the tie may be formed in any desired length, which length will be generally chosen in accordance with standard wall and form thicknesses and dependent upon whether waling strips and stiffbacking are to be utilized or whether just waling is utilized.

It may thus be seen that the objects of the invention set forth above as well as those made apparent from the preceding disclosure are sufficiently attained. Modifications to the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all modifications to the disclosed embodiments of the invention as well as other embodiments thereof which do not depart from the spirit and scope of the invention.

What is claimed is:

l. A tie rod for concrete forms comprising a length of wire of predetermined diameter having adjacent each end thereof a length of substantially square crosssection outwardly subtended by an annular flange, said flanges being integral with said rod, said flanges being of greater diameter than the diameter of said wire and at least as great as the cross-section diagonal of said square length whereby said flanges provide surfaces extending outwardly from each edge of said square section.

2. The rod of claim 1 wherein the cross-sectional area of said substantially square section is essentially the .Lsame as the cross-sectional area of the wire.

3. The rod of claim 1 wherein the dimension across any surface of said substantially square section is less each end of said wire adapted to be engaged by a tool. t 

1. A tie rod for concrete forms comprising a length of wire of predetermined diameter having adjacent each end thereof a length of substantially square cross-section outwardly subtended by an annular flange, said flanges being integral with said rod, said flanges being of greater diameter than the diameter of said wire and at least as great as the cross-section diagonal of said square length whereby said flanges provide surfaces extending outwardly from each edge of said square section.
 2. The rod of claim 1 wherein the cross-sectional area of said substantially square section is essentially the same as the cross-sectional area of the wire.
 3. The rod of claim 1 wherein the dimension across any surface of said substantially square section is less than the diameter of said wire.
 4. The tie rod of claim 1 further defined for the provision of a length of wire outwardly of said flanges at each end of said wire adapted to be engaged by a tool. 